Polyphenol Extraction Using Microwaves and Pressured Liquid Condition from Cupuaçu Seed By-Product: Optimization and Comparative Study

Cupuaçu (Theobroma grandiflorum Schum.) is an Amazonian fruit rich in antioxidants potential due to its phenolic compounds. Its seeds produce cupulate, a chocolate-like product, and the residue remains rich in biocompounds. This study aimed to optimize and compare microwave-assisted (MAE) and high pressure/temperature extraction (HPTE) of polyphenolic and flavonoid compounds from cupuaçu seed by-products. A Box-Behnken 33 factorial design assessed the influence of extraction time, solid/liquid ratio, and ethanol concentration. Responses included total polyphenol content, total flavonoid content, and anti-radical power via the ABTS (2,2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid) method. In optimum conditions, MAE had the highest total polyphenol content and HPTE for flavonoids. Optimal conditions for both methods were 65% (m/v) ethanol concentration, 45 min extraction time, and 0.03 g mL-1 solid/liquid ratio. MAE and HPTE achieved greater recovery of (–)-epicatechin and (–)-epigallocatechin-3-gallate compared to percolation. Both techniques proved viable for recovering polyphenols from cupuaçu seed by-products, in less time and with less solvent. Thus, cupuaçu by-products can be a sustainable and functional food source, with MAE and HPTE providing high yields and quality extracts rich in polyphenols.